Contents. 1  Calf rash AND Forearm rash: Causes of All Symptoms. 2  Calf rash OR Forearm rash: Causes of Any Symptom. 3  Calf rash: Causes.  Calf rash: 1  Introduction. Forearm rash: Causes.  Forearm rash: 1  Introduction. Calf rash and Forearm rash and Behind knee rash (15 causes)  Calf rash and Forearm rash and Finger rash (15 causes) Calf rash and Forearm rash and Foot rash (15 causes) Calf rash and Forearm rash and Groin rash (15 causes) Calf rash and Forearm rash and Hand rash (15 causes) Calf rash and Forearm rash and Knee rash (15 causes) Calf rash and Forearm rash and Kneecap rash (15 causes)
Gas in the digestive tract - the esophagus, stomach, small intestine, and large intestine - comes from two sources: 1  Swallowed air.  Normal breakdown of certain undigested foods by harmless bacteria naturally present in the large intestine, also called the colon.
A small amount of intestinal gas is absorbed into the blood from the intestine and is eliminated in the breath. The gas that is not used up by bacteria or eliminated in the breath must be passed. Passing gas relies on the functioning of the intestinal muscles.